Source 1primary paper2011Biochemical Journal
Toolkit/H2B-tKR
H2B-tKR
Also known as: histone H2B-tKR, tandem KillerRed
Taxonomy: Mechanism Branch / Architecture. Workflows sit above the mechanism and technique branches rather than replacing them.
Summary
H2B-tKR is a chromatin-targeted phototoxic construct in which histone H2B is fused to tandem KillerRed to control cell division with green light. Upon illumination, it induces nuclear damage-associated mitotic defects, including chromosome nondisjunction during metaphase, and can transiently block proliferation.
Usefulness & Problems
Why this is useful
This construct is useful for optically perturbing cell division with spatial and temporal control by restricting phototoxic activity to chromatin through histone H2B fusion. The cited work also indicates utility in vivo, where tissue-specific expression in transgenic Xenopus embryos combined with green-light illumination retards development of the expressing tissues.
Source:
We demonstrated that H2B-tKR-expressing cells behave normally in the dark, but transiently cease proliferation following green-light illumination.
Source:
In transgenic Xenopus embryos expressing H2B-tKR under the control of tissue-specific promoters, we observed clear retardation of the development of these tissues in green-light-illuminated tadpoles.
Source:
We believe that H2B-tKR represents a novel optogenetic tool, which can be used to study mitosis and meiosis progression per se, as well as to investigate the roles of specific cell populations in development, regeneration and carcinogenesis in vivo.
Problem solved
H2B-tKR addresses the problem of how to acutely disrupt mitosis and proliferation in selected cells or tissues using light rather than constitutive genetic or pharmacological perturbation. The evidence specifically supports its use to induce light-dependent mitotic failure and developmental retardation in expressing tissues.
Problem links
Need precise spatiotemporal control with light input
DerivedH2B-tKR is a chromatin-targeted phototoxic construct in which histone H2B is fused to tandem KillerRed to control cell division with green light. Upon illumination, it induces nuclear damage-associated mitotic defects, including chromosome nondisjunction during metaphase, and can transiently block proliferation.
Taxonomy & Function
Primary hierarchy
Mechanism Branch
Architecture: A reusable architecture pattern for arranging parts into an engineered system.
Mechanisms
chromatin targeting via histone h2b fusiongenomic dna damage inductionlight-triggered phototoxicityTechniques
Structural CharacterizationTarget processes
No target processes tagged yet.
Input: Light
Implementation Constraints
cofactor dependency: cofactor requirement unknownencoding mode: genetically encodedimplementation constraint: context specific validationimplementation constraint: spectral hardware requirementoperating role: actuator
The construct consists of histone H2B fused to tandem KillerRed, which targets the phototoxic module to chromatin. Reported implementations include expression in cells and transgenic Xenopus embryos, with tissue-specific promoters used for in vivo targeting; the perturbation is triggered by green-light illumination.
The evidence provided comes from a single 2011 study, so independent replication is not established here. Quantitative performance parameters such as illumination dose, reversibility beyond transient proliferation arrest, damage spectrum, and cross-system generalizability are not provided in the supplied evidence.
Validation
Cell-freeBacteriaMammalianMouseHumanTherapeuticIndep. Replication
Observations
successMammalian Cell Lineapplication demo
cell division after green-light illumination
Inferred from claim c2 during normalization. In cultured mammalian cells, H2B-tKR enables complete light-induced blockage of cell division for approximately 24 hours, after which cells return to a normal division rate. Derived from claim c2. Quoted text: Complete light-induced blockage of cell division for approx. 24 h was observed in cultured mammalian cells that were either transiently or stably transfected with H2B-tKR. Illuminated cells then returned to normal division rate.
Source:
duration of complete blockage of cell division24 h
successMammalian Cell Lineapplication demo
cell division after green-light illumination
Inferred from claim c2 during normalization. In cultured mammalian cells, H2B-tKR enables complete light-induced blockage of cell division for approximately 24 hours, after which cells return to a normal division rate. Derived from claim c2. Quoted text: Complete light-induced blockage of cell division for approx. 24 h was observed in cultured mammalian cells that were either transiently or stably transfected with H2B-tKR. Illuminated cells then returned to normal division rate.
Source:
duration of complete blockage of cell division24 h
successMammalian Cell Lineapplication demo
cell division after green-light illumination
Inferred from claim c2 during normalization. In cultured mammalian cells, H2B-tKR enables complete light-induced blockage of cell division for approximately 24 hours, after which cells return to a normal division rate. Derived from claim c2. Quoted text: Complete light-induced blockage of cell division for approx. 24 h was observed in cultured mammalian cells that were either transiently or stably transfected with H2B-tKR. Illuminated cells then returned to normal division rate.
Source:
duration of complete blockage of cell division24 h
successMammalian Cell Lineapplication demo
cell division after green-light illumination
Inferred from claim c2 during normalization. In cultured mammalian cells, H2B-tKR enables complete light-induced blockage of cell division for approximately 24 hours, after which cells return to a normal division rate. Derived from claim c2. Quoted text: Complete light-induced blockage of cell division for approx. 24 h was observed in cultured mammalian cells that were either transiently or stably transfected with H2B-tKR. Illuminated cells then returned to normal division rate.
Source:
duration of complete blockage of cell division24 h
successMammalian Cell Lineapplication demo
cell division after green-light illumination
Inferred from claim c2 during normalization. In cultured mammalian cells, H2B-tKR enables complete light-induced blockage of cell division for approximately 24 hours, after which cells return to a normal division rate. Derived from claim c2. Quoted text: Complete light-induced blockage of cell division for approx. 24 h was observed in cultured mammalian cells that were either transiently or stably transfected with H2B-tKR. Illuminated cells then returned to normal division rate.
Source:
duration of complete blockage of cell division24 h
successMammalian Cell Lineapplication demo
cell division after green-light illumination
Inferred from claim c2 during normalization. In cultured mammalian cells, H2B-tKR enables complete light-induced blockage of cell division for approximately 24 hours, after which cells return to a normal division rate. Derived from claim c2. Quoted text: Complete light-induced blockage of cell division for approx. 24 h was observed in cultured mammalian cells that were either transiently or stably transfected with H2B-tKR. Illuminated cells then returned to normal division rate.
Source:
duration of complete blockage of cell division24 h
successMammalian Cell Lineapplication demo
cell division after green-light illumination
Inferred from claim c2 during normalization. In cultured mammalian cells, H2B-tKR enables complete light-induced blockage of cell division for approximately 24 hours, after which cells return to a normal division rate. Derived from claim c2. Quoted text: Complete light-induced blockage of cell division for approx. 24 h was observed in cultured mammalian cells that were either transiently or stably transfected with H2B-tKR. Illuminated cells then returned to normal division rate.
Source:
duration of complete blockage of cell division24 h
Supporting Sources
Ranked Claims
Illumination of H2B-tKR-expressing cells during metaphase is associated with chromosome nondisjunction.
Notably, nondisjunction of chromosomes was observed for cells that were illuminated during metaphase.
Illumination of H2B-tKR-expressing cells during metaphase is associated with chromosome nondisjunction.
Notably, nondisjunction of chromosomes was observed for cells that were illuminated during metaphase.
Illumination of H2B-tKR-expressing cells during metaphase is associated with chromosome nondisjunction.
Notably, nondisjunction of chromosomes was observed for cells that were illuminated during metaphase.
Illumination of H2B-tKR-expressing cells during metaphase is associated with chromosome nondisjunction.
Notably, nondisjunction of chromosomes was observed for cells that were illuminated during metaphase.
Illumination of H2B-tKR-expressing cells during metaphase is associated with chromosome nondisjunction.
Notably, nondisjunction of chromosomes was observed for cells that were illuminated during metaphase.
Illumination of H2B-tKR-expressing cells during metaphase is associated with chromosome nondisjunction.
Notably, nondisjunction of chromosomes was observed for cells that were illuminated during metaphase.
Illumination of H2B-tKR-expressing cells during metaphase is associated with chromosome nondisjunction.
Notably, nondisjunction of chromosomes was observed for cells that were illuminated during metaphase.
H2B-tKR-expressing cells behave normally in the dark but transiently cease proliferation following green-light illumination.
We demonstrated that H2B-tKR-expressing cells behave normally in the dark, but transiently cease proliferation following green-light illumination.
H2B-tKR-expressing cells behave normally in the dark but transiently cease proliferation following green-light illumination.
We demonstrated that H2B-tKR-expressing cells behave normally in the dark, but transiently cease proliferation following green-light illumination.
H2B-tKR-expressing cells behave normally in the dark but transiently cease proliferation following green-light illumination.
We demonstrated that H2B-tKR-expressing cells behave normally in the dark, but transiently cease proliferation following green-light illumination.
H2B-tKR-expressing cells behave normally in the dark but transiently cease proliferation following green-light illumination.
We demonstrated that H2B-tKR-expressing cells behave normally in the dark, but transiently cease proliferation following green-light illumination.
H2B-tKR-expressing cells behave normally in the dark but transiently cease proliferation following green-light illumination.
We demonstrated that H2B-tKR-expressing cells behave normally in the dark, but transiently cease proliferation following green-light illumination.
H2B-tKR-expressing cells behave normally in the dark but transiently cease proliferation following green-light illumination.
We demonstrated that H2B-tKR-expressing cells behave normally in the dark, but transiently cease proliferation following green-light illumination.
H2B-tKR-expressing cells behave normally in the dark but transiently cease proliferation following green-light illumination.
We demonstrated that H2B-tKR-expressing cells behave normally in the dark, but transiently cease proliferation following green-light illumination.
In transgenic Xenopus embryos expressing H2B-tKR under tissue-specific promoters, green-light illumination retards development of the expressing tissues.
In transgenic Xenopus embryos expressing H2B-tKR under the control of tissue-specific promoters, we observed clear retardation of the development of these tissues in green-light-illuminated tadpoles.
In transgenic Xenopus embryos expressing H2B-tKR under tissue-specific promoters, green-light illumination retards development of the expressing tissues.
In transgenic Xenopus embryos expressing H2B-tKR under the control of tissue-specific promoters, we observed clear retardation of the development of these tissues in green-light-illuminated tadpoles.
In transgenic Xenopus embryos expressing H2B-tKR under tissue-specific promoters, green-light illumination retards development of the expressing tissues.
In transgenic Xenopus embryos expressing H2B-tKR under the control of tissue-specific promoters, we observed clear retardation of the development of these tissues in green-light-illuminated tadpoles.
In transgenic Xenopus embryos expressing H2B-tKR under tissue-specific promoters, green-light illumination retards development of the expressing tissues.
In transgenic Xenopus embryos expressing H2B-tKR under the control of tissue-specific promoters, we observed clear retardation of the development of these tissues in green-light-illuminated tadpoles.
In transgenic Xenopus embryos expressing H2B-tKR under tissue-specific promoters, green-light illumination retards development of the expressing tissues.
In transgenic Xenopus embryos expressing H2B-tKR under the control of tissue-specific promoters, we observed clear retardation of the development of these tissues in green-light-illuminated tadpoles.
In transgenic Xenopus embryos expressing H2B-tKR under tissue-specific promoters, green-light illumination retards development of the expressing tissues.
In transgenic Xenopus embryos expressing H2B-tKR under the control of tissue-specific promoters, we observed clear retardation of the development of these tissues in green-light-illuminated tadpoles.
In transgenic Xenopus embryos expressing H2B-tKR under tissue-specific promoters, green-light illumination retards development of the expressing tissues.
In transgenic Xenopus embryos expressing H2B-tKR under the control of tissue-specific promoters, we observed clear retardation of the development of these tissues in green-light-illuminated tadpoles.
Green-light illumination of H2B-tKR-expressing nuclei causes immediate XRCC1 redistribution, indicating massive light-induced genomic DNA damage.
XRCC1 (X-ray cross complementing factor 1) showed immediate redistribution in the illuminated nuclei of H2B-tKR-expressing cells, indicating massive light-induced damage of genomic DNA.
Green-light illumination of H2B-tKR-expressing nuclei causes immediate XRCC1 redistribution, indicating massive light-induced genomic DNA damage.
XRCC1 (X-ray cross complementing factor 1) showed immediate redistribution in the illuminated nuclei of H2B-tKR-expressing cells, indicating massive light-induced damage of genomic DNA.
Green-light illumination of H2B-tKR-expressing nuclei causes immediate XRCC1 redistribution, indicating massive light-induced genomic DNA damage.
XRCC1 (X-ray cross complementing factor 1) showed immediate redistribution in the illuminated nuclei of H2B-tKR-expressing cells, indicating massive light-induced damage of genomic DNA.
Green-light illumination of H2B-tKR-expressing nuclei causes immediate XRCC1 redistribution, indicating massive light-induced genomic DNA damage.
XRCC1 (X-ray cross complementing factor 1) showed immediate redistribution in the illuminated nuclei of H2B-tKR-expressing cells, indicating massive light-induced damage of genomic DNA.
Green-light illumination of H2B-tKR-expressing nuclei causes immediate XRCC1 redistribution, indicating massive light-induced genomic DNA damage.
XRCC1 (X-ray cross complementing factor 1) showed immediate redistribution in the illuminated nuclei of H2B-tKR-expressing cells, indicating massive light-induced damage of genomic DNA.
Green-light illumination of H2B-tKR-expressing nuclei causes immediate XRCC1 redistribution, indicating massive light-induced genomic DNA damage.
XRCC1 (X-ray cross complementing factor 1) showed immediate redistribution in the illuminated nuclei of H2B-tKR-expressing cells, indicating massive light-induced damage of genomic DNA.
Green-light illumination of H2B-tKR-expressing nuclei causes immediate XRCC1 redistribution, indicating massive light-induced genomic DNA damage.
XRCC1 (X-ray cross complementing factor 1) showed immediate redistribution in the illuminated nuclei of H2B-tKR-expressing cells, indicating massive light-induced damage of genomic DNA.
In cultured mammalian cells, H2B-tKR enables complete light-induced blockage of cell division for approximately 24 hours, after which cells return to a normal division rate.
Complete light-induced blockage of cell division for approx. 24 h was observed in cultured mammalian cells that were either transiently or stably transfected with H2B-tKR. Illuminated cells then returned to normal division rate.
duration of complete blockage of cell division 24 h
In cultured mammalian cells, H2B-tKR enables complete light-induced blockage of cell division for approximately 24 hours, after which cells return to a normal division rate.
Complete light-induced blockage of cell division for approx. 24 h was observed in cultured mammalian cells that were either transiently or stably transfected with H2B-tKR. Illuminated cells then returned to normal division rate.
duration of complete blockage of cell division 24 h
In cultured mammalian cells, H2B-tKR enables complete light-induced blockage of cell division for approximately 24 hours, after which cells return to a normal division rate.
Complete light-induced blockage of cell division for approx. 24 h was observed in cultured mammalian cells that were either transiently or stably transfected with H2B-tKR. Illuminated cells then returned to normal division rate.
duration of complete blockage of cell division 24 h
In cultured mammalian cells, H2B-tKR enables complete light-induced blockage of cell division for approximately 24 hours, after which cells return to a normal division rate.
Complete light-induced blockage of cell division for approx. 24 h was observed in cultured mammalian cells that were either transiently or stably transfected with H2B-tKR. Illuminated cells then returned to normal division rate.
duration of complete blockage of cell division 24 h
In cultured mammalian cells, H2B-tKR enables complete light-induced blockage of cell division for approximately 24 hours, after which cells return to a normal division rate.
Complete light-induced blockage of cell division for approx. 24 h was observed in cultured mammalian cells that were either transiently or stably transfected with H2B-tKR. Illuminated cells then returned to normal division rate.
duration of complete blockage of cell division 24 h
In cultured mammalian cells, H2B-tKR enables complete light-induced blockage of cell division for approximately 24 hours, after which cells return to a normal division rate.
Complete light-induced blockage of cell division for approx. 24 h was observed in cultured mammalian cells that were either transiently or stably transfected with H2B-tKR. Illuminated cells then returned to normal division rate.
duration of complete blockage of cell division 24 h
In cultured mammalian cells, H2B-tKR enables complete light-induced blockage of cell division for approximately 24 hours, after which cells return to a normal division rate.
Complete light-induced blockage of cell division for approx. 24 h was observed in cultured mammalian cells that were either transiently or stably transfected with H2B-tKR. Illuminated cells then returned to normal division rate.
duration of complete blockage of cell division 24 h
The authors present H2B-tKR as a novel optogenetic tool for studying mitosis, meiosis, and roles of specific cell populations in vivo.
We believe that H2B-tKR represents a novel optogenetic tool, which can be used to study mitosis and meiosis progression per se, as well as to investigate the roles of specific cell populations in development, regeneration and carcinogenesis in vivo.
The authors present H2B-tKR as a novel optogenetic tool for studying mitosis, meiosis, and roles of specific cell populations in vivo.
We believe that H2B-tKR represents a novel optogenetic tool, which can be used to study mitosis and meiosis progression per se, as well as to investigate the roles of specific cell populations in development, regeneration and carcinogenesis in vivo.
The authors present H2B-tKR as a novel optogenetic tool for studying mitosis, meiosis, and roles of specific cell populations in vivo.
We believe that H2B-tKR represents a novel optogenetic tool, which can be used to study mitosis and meiosis progression per se, as well as to investigate the roles of specific cell populations in development, regeneration and carcinogenesis in vivo.
The authors present H2B-tKR as a novel optogenetic tool for studying mitosis, meiosis, and roles of specific cell populations in vivo.
We believe that H2B-tKR represents a novel optogenetic tool, which can be used to study mitosis and meiosis progression per se, as well as to investigate the roles of specific cell populations in development, regeneration and carcinogenesis in vivo.
The authors present H2B-tKR as a novel optogenetic tool for studying mitosis, meiosis, and roles of specific cell populations in vivo.
We believe that H2B-tKR represents a novel optogenetic tool, which can be used to study mitosis and meiosis progression per se, as well as to investigate the roles of specific cell populations in development, regeneration and carcinogenesis in vivo.
The authors present H2B-tKR as a novel optogenetic tool for studying mitosis, meiosis, and roles of specific cell populations in vivo.
We believe that H2B-tKR represents a novel optogenetic tool, which can be used to study mitosis and meiosis progression per se, as well as to investigate the roles of specific cell populations in development, regeneration and carcinogenesis in vivo.
The authors present H2B-tKR as a novel optogenetic tool for studying mitosis, meiosis, and roles of specific cell populations in vivo.
We believe that H2B-tKR represents a novel optogenetic tool, which can be used to study mitosis and meiosis progression per se, as well as to investigate the roles of specific cell populations in development, regeneration and carcinogenesis in vivo.
Approval Evidence
1 source6 linked approval claimsfirst-pass slug h2b-tkr
In the present study we used H2B (histone H2B)-tKR (tandem KillerRed) as an active tool to affect cell division with light.
Source:
cellular phenotypesupports
Illumination of H2B-tKR-expressing cells during metaphase is associated with chromosome nondisjunction.
Notably, nondisjunction of chromosomes was observed for cells that were illuminated during metaphase.
Source:
functional effectsupports
H2B-tKR-expressing cells behave normally in the dark but transiently cease proliferation following green-light illumination.
We demonstrated that H2B-tKR-expressing cells behave normally in the dark, but transiently cease proliferation following green-light illumination.
Source:
in vivo effectsupports
In transgenic Xenopus embryos expressing H2B-tKR under tissue-specific promoters, green-light illumination retards development of the expressing tissues.
In transgenic Xenopus embryos expressing H2B-tKR under the control of tissue-specific promoters, we observed clear retardation of the development of these tissues in green-light-illuminated tadpoles.
Source:
mechanistic indicatorsupports
Green-light illumination of H2B-tKR-expressing nuclei causes immediate XRCC1 redistribution, indicating massive light-induced genomic DNA damage.
XRCC1 (X-ray cross complementing factor 1) showed immediate redistribution in the illuminated nuclei of H2B-tKR-expressing cells, indicating massive light-induced damage of genomic DNA.
Source:
temporal effectsupports
In cultured mammalian cells, H2B-tKR enables complete light-induced blockage of cell division for approximately 24 hours, after which cells return to a normal division rate.
Complete light-induced blockage of cell division for approx. 24 h was observed in cultured mammalian cells that were either transiently or stably transfected with H2B-tKR. Illuminated cells then returned to normal division rate.
Source:
tool positioningsupports
The authors present H2B-tKR as a novel optogenetic tool for studying mitosis, meiosis, and roles of specific cell populations in vivo.
We believe that H2B-tKR represents a novel optogenetic tool, which can be used to study mitosis and meiosis progression per se, as well as to investigate the roles of specific cell populations in development, regeneration and carcinogenesis in vivo.
Source:
Comparisons
Source-backed strengths
According to the cited study, H2B-tKR-expressing cells behave normally in the dark, indicating low baseline perturbation before illumination. Green-light exposure produces a clear functional effect, including transient cessation of proliferation and metaphase-associated chromosome nondisjunction, and the approach was extended to transgenic Xenopus embryos under tissue-specific promoters.
Compared with mMORp
H2B-tKR and mMORp address a similar problem space.
Shared frame: same top-level item type; same primary input modality: light
Compared with optogenetic probes
H2B-tKR and optogenetic probes address a similar problem space.
Shared frame: same top-level item type; same primary input modality: light
Compared with organoid fusion
H2B-tKR and organoid fusion address a similar problem space.
Shared frame: same top-level item type; same primary input modality: light
Ranked Citations
- 1.